1. Field of the Invention
The present invention relates in general to multistage automatic transmissions for wheeled motor vehicle, and more particularly to the multistage automatic transmissions of a constant-mesh type. More specifically, the present invention is concerned with the multistage automatic transmission having a speed change control system incorporated therewith.
2. Description of the Related Art
In order to clarify the task of the present invention, one of the multistage automatic transmissions of the above-mentioned type will be briefly described, which is disclosed in Japanese Laid-open Patent Application (Tokkai) 2002-357267. In this transmission, there are arranged first and second input shafts, synchromesh gear pairs, a first clutch for establishing ON/OFF connection between an associated engine and the first input shaft and a second clutch for establishing ON/OFF connection between the engine and the second shaft. By switching the first and second clutches, a speed change is carried out in the transmission. In this transmission, there are further provided mechanisms by which the ON/OFF operation of each clutch and a gear selection operation are automatically carried out.